Agree, if this hits 2018 it will keep the current momentum continuous and then some. I feel like it could do what Zelda and Mario did combined.

Pokemon Sun and Moon were not ambitious. They just changed the formula slightly. 

I just really hope that they go all out with this game. Take chances with the story and scenarios, impress with the visuals, and keep the battle system as amazing as it has been for decades. This is going to be the first HD Mainline Pokemon Game, they'd better come out swinging.

Pokemon Prism and Uranium are some of the best Pokemon games ever made, and they're not by Nintendo. I think what helps those games is that they're very varied in structure and scenario and they're true to themselves. Stuff like Ride Pokemon, Ultra Beasts, etc. feel like life support for the sake of creativity and innovation in the series and I for one, am not a fan of their inclusion. But we'll see where they go with this new game.

Sun/Moon and Black 2/White 2 were harder than all the games since Gen 1

PokeRides are vital. HM's were terrible. And Alolan forms were something that needed to happen a long time ago

It'll be good. Especially since the main team for Pokemon hasn't made a Pokemon game since X/Y. We've seen some of the new models as per Pokemon Go. So that'll give you a preview of how the Pokemon models will look in gen 8. For those unaware: Sun/Moon and US/UM were made by Pokemon's second team. This team is considered the "creative team" that makes what you might call the definitive versions of Pokemon games. So they've worked on: Crystal, Emerald, FireRed/LeafGreen, Platinum, HG/SS, Black 2/White 2, and OR/AS

I just hope that the encounter system finally gets reworked. Don't just have the player walk through grass and then transition to a battle. There's no reason at this point to not have the Pokemon visible while walking around. Avoiding Pokemon could actually be a challenge and fun for those who want, instead of just having encounters decided by a random number generator.

Source?

would be for sure a big hit

Pokerides aren't vital. HM's were terrible, Alolan forms were cool. I'm more talking about the scenarios of Pokemon and the story which are trying too hard and they end up not being that interesting. Pokerides just seem very cheesy and kind of disrupt that raw connection between trainer and Pokemon that I felt Pokemon HMs offered. I just feel HMs made you build a skillset a bit more cautiously and that consequence helped add to the reality of the game. Now, Pokemon was never a hard game per se, but it's become easier and easier as they make it more and more convenient for the player.